My husband is 60 yrs, cardiac pt 2002 heart attach & quad bypass, w/33% heart damage, ascending aorta 4.3, EF 27-35%, long time Marlboro smoker, still smokes, has COPD and has an oxygen machine for sleep re: oxygen levels tested 77-89 during sleep x5 for 15min. Dr. said if EF tests next week is below 35% then defib surgery will be recommended. I've noticed his breathing to be more labored after bending over, walking up 3-4 steps.